Data.Extensible.Effect.Default

Default monad runners and MonadIO, MonadReader, MonadWriter, MonadState, MonadError instances

Documentation

type ReaderDef r = "Reader" >: ReaderEff r

mtl-compatible reader

runReaderDef :: Eff (ReaderDef r ': xs) a -> r -> Eff xs a

Specialised version of runReaderEff compatible with the MonadReader instance.

type StateDef s = "State" >: State s

mtl-compatible state

runStateDef :: Eff (StateDef s ': xs) a -> s -> Eff xs (a, s)

runStateEff specialised for the MonadState instance.

evalStateDef :: Eff (StateDef s ': xs) a -> s -> Eff xs a

evalStateEff specialised for the MonadState instance.

execStateDef :: Eff (StateDef s ': xs) a -> s -> Eff xs s

execStateEff specialised for the MonadState instance.

type WriterDef w = "Writer" >: WriterEff w

mtl-compatible writer

runWriterDef :: Monoid w => Eff (WriterDef w ': xs) a -> Eff xs (a, w)

runWriterDef specialised for the MonadWriter instance.

execWriterDef :: Monoid w => Eff (WriterDef w ': xs) a -> Eff xs w

execWriterDef specialised for the MonadWriter instance.

type MaybeDef = "Either" >: EitherEff ()

Same as EitherDef ()

runMaybeDef :: Eff (MaybeDef ': xs) a -> Eff xs (Maybe a)

Similar to runMaybeT, but on Eff

type EitherDef e = "Either" >: EitherEff e

mtl-compatible either effect

runEitherDef :: Eff (EitherDef e ': xs) a -> Eff xs (Either e a)

Similar to runExceptT, but on Eff

Orphan instances

(Monoid w, Associate Symbol (* -> *) "Writer" ((,) w) xs) => MonadWriter w (Eff Symbol xs)

Methods

writer :: (a, w) -> Eff Symbol xs a

tell :: w -> Eff Symbol xs ()

listen :: Eff Symbol xs a -> Eff Symbol xs (a, w)

pass :: Eff Symbol xs (a, w -> w) -> Eff Symbol xs a

Associate Symbol (* -> *) "State" (State s) xs => MonadState s (Eff Symbol xs)

Methods

get :: Eff Symbol xs s

put :: s -> Eff Symbol xs ()

state :: (s -> (a, s)) -> Eff Symbol xs a

Associate Symbol (* -> *) "Reader" ((:~:) * r) xs => MonadReader r (Eff Symbol xs)

Methods

ask :: Eff Symbol xs r

local :: (r -> r) -> Eff Symbol xs a -> Eff Symbol xs a

reader :: (r -> a) -> Eff Symbol xs a

Associate Symbol (* -> *) "Either" (Const * e) xs => MonadError e (Eff Symbol xs)

Methods

throwError :: e -> Eff Symbol xs a

catchError :: Eff Symbol xs a -> (e -> Eff Symbol xs a) -> Eff Symbol xs a

(Monoid e, Associate Symbol (* -> *) "Either" (Const * e) xs) => Alternative (Eff Symbol xs)

A bit dubious

Methods

empty :: Eff Symbol xs a

(<|>) :: Eff Symbol xs a -> Eff Symbol xs a -> Eff Symbol xs a

some :: Eff Symbol xs a -> Eff Symbol xs [a]

many :: Eff Symbol xs a -> Eff Symbol xs [a]

(Monoid e, Associate Symbol (* -> *) "Either" (Const * e) xs) => MonadPlus (Eff Symbol xs)

Methods

mzero :: Eff Symbol xs a

mplus :: Eff Symbol xs a -> Eff Symbol xs a -> Eff Symbol xs a

(MonadIO m, Associate Symbol (* -> *) "IO" m xs) => MonadIO (Eff Symbol xs)

Methods

liftIO :: IO a -> Eff Symbol xs a